294 Dr Sutherland on Currents in the Arctic Seas. 



ment of the climate, on the east side of the strait, arise from 

 the disposition the ice has to leave the coast, by which means 

 the water becomes exposed to the influence of the sun ; or 

 from currents of heated water from a more southern region. 

 He further remarks that its density here cannot be restored, 

 if once disturbed, without admixture with a large volume of 

 water somewhat above the mean density. 



Again referring to the observations of Sir Edward Parry 

 and those recorded in the tables, the author remarks, that 

 from these it will be seen that refrigeration has the effect of 

 precipitating the salts of sea-water ; and further, that it ap- 

 pears to him very probable that the temperature at which 

 water begins to expand by the continued application of cold, 

 is that at which saline and earthy matter begins to be preci- 

 pitated in solutions of the density of sea- water. 



From the immense depth to which icebergs extend in 

 Davis's Straits, and also from their vast number, the author 

 infers that the temperature of the water will be kept pretty 

 uniformly the same throughout a considerable part of its 

 depth, rarely exceeding + 32°, except at the surface, where 

 the action of the sun comes into operation, in which case the 

 water of greatest density from saline contents would always 

 occupy the lowest position. In illustration of his views, he 

 describes experiments on the freezing of sea-water of the 

 density 1*025, in glass tubes; and from these he infers that, 

 not only does congelation precipitate the saline matter in 

 water, but refrigeration also, at temperatures from 40° down 

 to 32°. With reference to the influence of the density of the 

 sea-water on currents, he remarks, that after the warm sea- 

 son has fairly set in in the Arctic seas, nothing is more com- 

 mon than to observe the surface-water, in hollowed-out lanes 

 or fissures of the land-ice, moving slowly towards the open 

 water at the edge of the fixed ice ; and this seaward motion 

 is altogether independent of tidal motion or oceanic current, 

 depending entirely upon the diminished density of the sur- 

 face-water. 



In conclusion, the author states that he does not know that 

 we are yet in a position to demonstrate the actual existence 

 of currents into the icy seas as well as out of them, but that 



